From patchwork Fri Mar 23 00:15:36 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Long Li X-Patchwork-Id: 10302539 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 40807600CC for ; Fri, 23 Mar 2018 00:17:38 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3169E285C4 for ; Fri, 23 Mar 2018 00:17:38 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 246F2285DA; Fri, 23 Mar 2018 00:17:38 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C2F54285C4 for ; Fri, 23 Mar 2018 00:17:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751758AbeCWAQ5 (ORCPT ); Thu, 22 Mar 2018 20:16:57 -0400 Received: from a2nlsmtp01-04.prod.iad2.secureserver.net ([198.71.225.38]:42518 "EHLO a2nlsmtp01-04.prod.iad2.secureserver.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751853AbeCWAQ4 (ORCPT ); Thu, 22 Mar 2018 20:16:56 -0400 Received: from linuxonhyperv2.linuxonhyperv.com ([107.180.71.197]) by : HOSTING RELAY : with SMTP id zAN9e6XdyYARIzAN9ehY94; Thu, 22 Mar 2018 17:15:55 -0700 x-originating-ip: 107.180.71.197 Received: from longli by linuxonhyperv2.linuxonhyperv.com with local (Exim 4.89_1) (envelope-from ) id 1ezAN9-0008Ir-DK; Thu, 22 Mar 2018 17:15:55 -0700 From: Long Li To: "K . Y . Srinivasan" , Haiyang Zhang , Stephen Hemminger , "James E . J . Bottomley" , "Martin K . Petersen" , devel@linuxdriverproject.org, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Long Li Subject: [PATCH 1/3] Vmbus: Add function to report available ring buffer to write in total ring size percentage Date: Thu, 22 Mar 2018 17:15:36 -0700 Message-Id: <20180323001538.31876-1-longli@linuxonhyperv.com> X-Mailer: git-send-email 2.15.1 X-CMAE-Envelope: MS4wfOMlhT6CUbBhekVNpPBE852wfm96Z32mMVTFv9G2RIOWmdiHTCNC9fUYp20cjpmEhkKoRJ2ZQtgV1tv4Ff3qIwjdmkh37K8IAmVjVBBUj/u6gqEQeAsj ngaZ6lrmL0XJE6SrX6KjCzds5wQavQcz03Knn2HNnHqoG4V7DZg+3DSYN/St2Knohyvt+FqkxzLqdtUaCyhSUp0hGM0rkhsRJFomMWEAFqe5j8TsM8Is6VId 0jfMyrJKM+t3IpBPJRK1jMtKM039cViX23sNu7T/fsPCL299RTSQLhIJNKibp1twhFx29Z8dkr7MqDZzeINLeNarNt+dkGLB7o30/98xiyOFU6y+URGx2I31 f8l/zxlGsrMecltHEIbG89B+mhooukh9Ir1SBQXcvfceI1Fw07VjHlwotDU7ygWHRTtTbnrH4Lbz69RcwbYRIRVi+bdRr6S5h8kyInqjgADDyxfcRDJMIZq9 9Ql4vg9ulCHg2/l+VRm6LhEccRDlHdfuuekMSvj8a+i6XRxRvc4I+iq86VY= Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Long Li Netvsc has a similar function to calculate how much ring buffer in percentage is available to write. This function is useful for storvsc and other vmbus devices. Define a similar function in vmbus to be used by storvsc. Signed-off-by: Long Li Reviewed-by: Haiyang Zhang --- drivers/hv/ring_buffer.c | 2 ++ include/linux/hyperv.h | 12 ++++++++++++ 2 files changed, 14 insertions(+) diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c index 8699bb969e7e..3c836c099a8f 100644 --- a/drivers/hv/ring_buffer.c +++ b/drivers/hv/ring_buffer.c @@ -227,6 +227,8 @@ int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info, ring_info->ring_buffer->feature_bits.value = 1; ring_info->ring_size = page_cnt << PAGE_SHIFT; + ring_info->ring_size_div10_reciprocal = + reciprocal_value(ring_info->ring_size / 10); ring_info->ring_datasize = ring_info->ring_size - sizeof(struct hv_ring_buffer); diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h index 2048f3c3b68a..eb7204851089 100644 --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.h @@ -36,6 +36,7 @@ #include #include #include +#include #define MAX_PAGE_BUFFER_COUNT 32 #define MAX_MULTIPAGE_BUFFER_COUNT 32 /* 128K */ @@ -121,6 +122,7 @@ struct hv_ring_buffer { struct hv_ring_buffer_info { struct hv_ring_buffer *ring_buffer; u32 ring_size; /* Include the shared header */ + struct reciprocal_value ring_size_div10_reciprocal; spinlock_t ring_lock; u32 ring_datasize; /* < ring_size */ @@ -155,6 +157,16 @@ static inline u32 hv_get_bytes_to_write(const struct hv_ring_buffer_info *rbi) return write; } +static inline u32 hv_get_avail_to_write_percent( + const struct hv_ring_buffer_info *rbi) +{ + u32 avail_write = hv_get_bytes_to_write(rbi); + + return reciprocal_divide( + (avail_write << 3) + (avail_write << 1), + rbi->ring_size_div10_reciprocal); +} + /* * VMBUS version is 32 bit entity broken up into * two 16 bit quantities: major_number. minor_number.